Bi-amp with same sort of amp?

I think it depends on whether you are biamping vertically or horizontally. For vertical biamping (bridging amp to mono) I would recommend staying with the exact same amps. If you are talking horizontal biamping, one amp fo bass the other for the mids and highs, I disagree. I have found that using amps from different manufacturers with different slew rates and different power outputs to not be a problem. I've used less expensive, more powerful amps like an Adcom (200wpc)on the bass, then driven the mids/highs with a lower powered Classe/ Counterpoint (100wpc) or such with very good results. I hope this helps.

Reason for asking is that I have experienced different
timing or pace in the same music, when listening to different amplifiers. E.g. I have a 100 w Class A amp
which is somewhat slower in the lower register, than
my home-built monoblocks, all are solid state ones.
The monoblocks have real good ability in the bass region,but as I built them more than 15 years ago(and although I have updated them), I dare not use them with the new speakers and in the long run, because of risk of ampfailure,which could be costly as this loudspeaker-project isn´t a cheap one.
(So, they may retire in the bedroom system).

Like you , I thought that I could buy a cheaper amp for the
subs(consider my loudspeakers as a sub- satellite system).
But I may rethink the idea of using different amps in the system. And that because I´m very sensitive to the pace of the music.
On the other hand, using top-class amps even for
the lower register, will cost a lot of money.

(I have played some music myself- if that matters).

So, if I state my question more clear,can you say that the
more complex a system gets, the more unpredictable it becomes. From that followes, that the possible combinations
of amps and cables and room treatment, whith a complex system,may never be optimized. Or, that at least it will take a very lot of time to get near your goal?
And are there some more experiences and opinions to this matter?
Of course,even if someone has failured, while trying to
combine different amps for bass, mids, and treble, in a synergetic way, please let me know!

Regards
Håkan

I have actually used amps to compensate for slew rates damping factors etc. I'm biamping Martin Logan Monoliths with Levinson Reference 20.0 monoblocks on top. They are what I would call "dark" amps. Very smooth, very refined--relatively low damping factor. They really sound good on the panels and have no problems with the impedance loads. On the bottom end I'm using Krell KMA 160. A bit more powerful, higher damping factor. These have better control in the bass end. For me, my speakers benefited from using different amps--and I selected the amps to do just this--but different speakers would certainly have different requirements, benefits, and drawbacks. It is nice to be able to taylor the amp individually for the low vs the high. I'm not very familiar with the VMPS--I have heard them--but that's all.